Aon (AON) 8-K Regulation FD Disclosure

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Exhibit 99.3

AON CORPORATION
VARIOUS SEGMENT INFORMATION—AFTER RECLASSIFICATION

			2002
(millions)			1st Qtr.			2nd Qtr.			3rd Qtr.			4th Qtr.			Full Year
REVENUE
	Risk & Insurance Brokerage Services		$	1,157		$	1,215		$	1,247		$	1,354		$	4,973
	Consulting			233			248			269			304			1,054
	Insurance Underwriting			649			750			718			684			2,801
	Corporate & Other			49			(91	)		12			24			(6	)
		Total Revenue	$	2,088		$	2,122		$	2,246		$	2,366		$	8,822
INCOME (LOSS) BEFORE INCOME TAXES
	Risk & Insurance Brokerage Services		$	189		$	144		$	209		$	249		$	791
	Consulting			27			23			26			44			120
	Insurance Underwriting			68			2			41			44			155
	Corporate & Other			(13	)		(153	)		(59	)		(48	)		(273	)
		Total Income Before Income Taxes	$	271		$	16		$	217		$	289		$	793
INCOME BEFORE INCOME TAXES—MARGINS
	Risk & Insurance Brokerage Services			16.3	%		11.9	%		16.8	%		18.4	%		15.9	%
	Consulting			11.6	%		9.3	%		9.7	%		14.5	%		11.4	%
	Insurance Underwriting			10.5	%		0.3	%		5.7	%		6.4	%		5.5	%
		Total Income Before Income Taxes—Margins		13.0	%		0.8	%		9.7	%		12.2	%		9.0	%
ORGANIC REVENUE GROWTH
	Risk & Insurance Brokerage Services			13	%		10	%		21	%		10	%		13	%
	Consulting			4	%		6	%		14	%		12	%		9	%
	Insurance Underwriting			17	%		23	%		7	%		4	%		11	%
		Total Organic Revenue Growth		14	%		14	%		15	%		9	%		12	%

			2001
			1st Qtr.			2nd Qtr.			3rd Qtr.			4th Qtr.			Full Year
REVENUE
	Risk & Insurance Brokerage Services		$	1,052		$	1,083		$	1,030		$	1,198		$	4,363
	Consulting			212			229			232			265			938
	Insurance Underwriting			628			609			641			643			2,521
	Corporate & Other			(81	)		(4	)		9			(70	)		(146	)
		Total Revenue	$	1,811		$	1,917		$	1,912		$	2,036		$	7,676
INCOME (LOSS) BEFORE INCOME TAXES
	Risk & Insurance Brokerage Services		$	166		$	79		$	142		$	178		$	565
	Consulting			24			24			29			49			126
	Insurance Underwriting			68			60			45			(5	)		168
	Corporate & Other			(210	)		(99	)		(83	)		(158	)		(550	)
		Total Income Before Income Taxes	$	48		$	64		$	133		$	64		$	309
INCOME (LOSS) BEFORE INCOME TAXES—MARGINS
	Risk & Insurance Brokerage Services			15.8	%		7.3	%		13.8	%		14.9	%		12.9	%
	Consulting			11.3	%		10.5	%		12.5	%		18.5	%		13.4	%
	Insurance Underwriting			10.8	%		9.9	%		7.0	%		-0.8	%		6.7	%
	Total Income Before Income Taxes—Margins			2.7	%		3.3	%		7.0	%		3.1	%		4.0	%
ORGANIC REVENUE GROWTH
	Risk & Insurance Brokerage Services			8	%		12	%		6	%		9	%		9	%
	Consulting			8	%		9	%		4	%		7	%		7	%
	Insurance Underwriting			5	%		1	%		8	%		8	%		5	%
		Total Organic Revenue Growth		7	%		8	%		7	%		9	%		8	%

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Exhibit 99.3

AON CORPORATION VARIOUS SEGMENT INFORMATION—AFTER RECLASSIFICATION